Figure 4. CTRP9 alleviates ox-LDL-induced VSMC-derived foam cell necroptosis. Human aortic smooth muscle cells (HASMCs) were treated for 72 h with 5 µg/mL cyclodextrin-cholesterol complex to establish VSMC-derived foam cells, which were subsequently exposed to different doses of CTRP9 (0–10 μg/mL) in the presence of ox-LDL (10 μg/mL) or left untreated (control) for 24 h. (a) The morphology of VSMC-derived foam cells was analyzed using transmission electron microscopy. (b) The proportion of PI-positive cells was determined quantitatively. (c) Western blotting was performed to examine the protein levels of MLKL, p-MLKL, RIP3, RIP1, and p-RIP1. (d) Quantitative analysis of necroptosis-associated protein expression. (e) Real-time PCR analysis of the mRNA levels of atherosclerosis-related factors. Data are presented as mean ± SD of three independent experiments. **p < 0.01 vs. the control group; ##p < 0.01 vs. the 10 μg/mL ox-LDL group.